This is my first knitting effort since school...I really dont get what to do..I understand how to read my size...so I purl 4, then do I add a stitch? inc in next st...I dont understand this bit? then it says 0 times..? so does this not apply to my size? then again I purl 4 ( I get that) and again I increase in next stitch?? not sure what to do...add a stitch? then purl 3 & again inc ?? again 0 times?? so do I ignore this instruction? then purl 4. then just 16 stitches at end, I presume I just purl these???